Crew seats used in certain military and emergency vehicles and aircraft are designed with the intent to prevent injury to the occupant from impulse loads associated with crashes and other unexpected high acceleration events. For example, so-called variable-displacement seats incorporate mechanisms to attenuate the lethal energy pulse levels that may result from an under-vehicle mine blast or an aircraft hard landing. In such ultra-high acceleration events it is crucial that the occupant stay positively restrained in the seat at all times to prevent rebound injuries. Accordingly, such seats typically utilize multi-point belt restraint systems, minimally including two lap belts and two shoulder belts that connect to a centrally located buckle or latch.
However, crew members utilizing military and emergency vehicles that incorporate such seats often wear various forms of emergency and tactical gear. Examples include fire resistant jackets, breathing equipment, and ballistic armor vests. Gear of this type can be quite bulky and restrictive to movement, in some cases interfering with a crew member's ability to perform necessary and routine tasks such as attaching a belt restraint system. In particular, the shoulder straps of a multi-point restraint system typically extend from behind the seat through a guide located at or near the top of the seat back. Once a crew member is seated, the shoulder straps can become trapped between the occupant's back and the seat, or in some cases can slip around the side of the seat and behind the seat back. In either situation, it can be difficult or impossible for a seated occupant wearing restrictive gear to reach and then don the shoulder belts without assistance from another crew member. In addition, the confined seating quarters typical of vehicles and aircraft that utilize crew seats with multi-point belt restraint systems make performing such tasks even more difficult.
Accordingly, a need exists for a belt restraint system suitable for use on a crew seat of a vehicle or aircraft exposed to high acceleration conditions that can accommodate the use of bulky and restrictive equipment worn by a crew member. A further need exists for such a belt restraint system that can be readily reached and attached by a seated crew member without assistance.